Many devices are known for purposes of stopping machinery after machinery experiences a predetermined number of revolutions of its components or, alternatively, following an axial movement of a component along a predetermined distance. U.S. Pat. No. 4,721,196, which issued to Layer, et al on Jan. 26, 1988 describes an overtravel stop for rotary shaft. The overtravel stop includes a fixed stop having at least a pair of stop jaws disposed at different radii from the axis of the rotary shaft. A follower member is provided about the rotary shaft and is adapted to rotate with the shaft within a selected travel limit. The follower member is associated with a stop member having at least a pair of stop jaws disposed at the same different radii as the stop jaws on the fixed stop. The follower member is rotationally shiftable with respect to the shaft when the shaft reaches its travel limit. The stop member is axially movable into engagement with the fixed stop when the follower member rotationally shifts relative to the shaft. At least some of the stop jaws have negative rake angles and a shock absorber is provided behind the fixed stop.
Other mechanisms are disclosed in patents such as Gillingham, et al U.S. Pat. No. 4,641,737 issued Feb. 10, 1987 and in French Patent 1,157,306 published May 28, 1958. In the prior art generally, an adjust feature for changing the final stop position is not easily obtainable, especially where there is a need to change the stop position on a continuously variable basis.